Starting my engine on a stand, issues arose |
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Starting my engine on a stand, issues arose |
malcolm2 |
Sep 29 2020, 06:16 AM
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#41
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Advanced Member Group: Members Posts: 2,747 Joined: 31-May 11 From: Nashville Member No.: 13,139 Region Association: South East States |
I have built a fresh 2.0 and borrowed a set of weber 40s to get her running, broken-in etc....
I bought a new single vacuum distributor with the flame thrower 3 module inside. Also bought the Petronix coil. I built up oil pressure, then connected the gas lines, fuel pump, and coil. Tach and timing light too. After a few tries, she started. As expected running very ruff. Back-firing thru the carbs. I loosened the distributor and tried to make some adjustments. That seemed to help the back-firing a bit, but not totally. I got the idle timing to what looks like 7 btdc, but it is tuff to work everything without a helper. I know next to nothing about these carbs, and about the same amount to tune them enough to bench run the engine, but I am looking into that. Any help would be appreciated on the carbs. I got it idling, again, very ruff. So I wanted to do the cam break in, so I rev'd it up to about 3000 and held there. Maybe a minute and the revs dropped and I had to putz with the accelerator to keep her going. Again up to 3000, same thing revs dropped. I have a note in to my distributor vendor about how this "rev limiter" on this module works. So three things here. She is still running ruff, back-firing etc...and there is the high rev cut-off. Lastly the carbs, any quick checks or adjustments there? Any thoughts or suggestions? |
Mark Henry |
Sep 29 2020, 06:53 AM
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#42
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that's what I do! Group: Members Posts: 20,065 Joined: 27-December 02 From: Port Hope, Ontario Member No.: 26 Region Association: Canada |
Do you have a snail sync tool? Sounds like a sync issue.
Bad linkage adjustment as well, the flat fours are super sensitive to sync issues. What rev limiter? They cut off at high RPM and shouldn't cause an issue, but the bosch rotors have a resistor that can go bad. Just swap out a regular rotor. |
malcolm2 |
Sep 29 2020, 08:50 AM
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#43
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Advanced Member Group: Members Posts: 2,747 Joined: 31-May 11 From: Nashville Member No.: 13,139 Region Association: South East States |
Do you have a snail sync tool? Sounds like a sync issue. Bad linkage adjustment as well, the flat fours are super sensitive to sync issues. What rev limiter? I will see about getting the snail tool today. The rev limiter is within the electronic module. appears to be adjustable. Wonder what it is adjusted to? This came from the vendor: "If you are wondering, the Pertronix Flamethrower III module has a couple of advantages over the original Pertronix. First, the Flamethrower III module changes dwell as needed. It also senses when the key is on but the engine is not running, which used to burn out the original Pertronix! The Pertronix III is immune to this annoying problem! The Pertronix III has a digital rev limiter that you can set to the RPM that you feel is best! We believe these features are worth the additional money over the original version of the Pertronix module. The Pertronix 3 SVDA Distributor, 12 VOLT is designed to run with a low impedance (0.32 ohm) coil for best operation" |
Mark Henry |
Sep 29 2020, 09:17 AM
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#44
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that's what I do! Group: Members Posts: 20,065 Joined: 27-December 02 From: Port Hope, Ontario Member No.: 26 Region Association: Canada |
Do you have a snail sync tool? Sounds like a sync issue. Bad linkage adjustment as well, the flat fours are super sensitive to sync issues. What rev limiter? I will see about getting the snail tool today. THe rev limiter is within the electronic module. THis came from the vendor: "If you are wondering, the Pertronix Flamethrower III module has a couple of advantages over the original Pertronix. First, the Flamethrower III module changes dwell as needed. It also senses when the key is on but the engine is not running, which used to burn out the original Pertronix! The Pertronix III is immune to this annoying problem! The Pertronix III has a digital rev limiter that you can set to the RPM that you feel is best! We believe these features are worth the additional money over the original version of the Pertronix module. The Pertronix 3 SVDA Distributor, 12 VOLT is designed to run with a low impedance (0.32 ohm) coil for best operation" The rev limiter shouldn't be an issue if it's set correctly, pertronix either works or it doesn't. |
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